Identification of Groundwater Potential Zones in Wakawali Watershed Using Remote Sensing and Geographic Information System (GIS)

Abstract

Groundwater is a crucial source of fresh water that is stored below the Earth's surface in the saturated zone, filling gaps and spaces in soil and geological formations.  Groundwater is a hidden natural resource that cannot be directly detected, therefore mapping of this resource can be challenging task. In the present study, remote sensing and geographic information systems techniques were collectively used to categorize groundwater potential zones in the Wakawali watershed of Ratnagiri District.  In this study, SRTM DEM of 30 m resolution and conventional data was used to generate thematic layers such as slope, drainage density, lithology, geomorphology, soil and rainfall. Weightage percentages to each thematic layer were assigned according to their relative importance to groundwater potentiality using AHP technique. Further, integrated using “weighted sum” tool in Arc-GIS software. The outcomes of the groundwater potential map of the study area were classified into five zones viz., very poor, poor, moderately poor, good, very good contributing to 3.18%, 17.68%, 30.86%, 31.18% and 17.11% respectively. The study conclude that the remote sensing and Geographic Information System is a significant tool for land and water resource studies as well as preparation of water resources development plans, so as to prepare economically viable plans.